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Re: GE primer (was: easier to swallow?) (fwd)




I am often overzealous in crossposting newsworthy articles  to this list
and I will try to restrain myself in the future but this one so clearly
explains and demistifies current GE issues and practices that I though
that many of you would benefit from reading it. LL
This exists at:
http://metalab.unc.edu/london/orgfarm/issues-and-news/issues/GE.Primer

---------- Forwarded message ----------
Date: Sun, 25 Jul 1999 10:21:27 EST
From: "E. Ann Clark, Associate Professor" <ACLARK@plant.uoguelph.ca>
To: sanet-mg@ces.ncsu.edu
Subject: Re:  GE primer (was: easier to swallow?)

Beth:  yes, I'm increasingly convinced that it really is the process, 
and not the product, that is suspect.  Understand that I am no expert 
on this, my field is pasture and grazing management, so I am 
repeating what I've been told or have read.

The issue is the presumption (some might say arrogance or even 
ignorance) that genes can be identified as having causal influences 
on some trait, such that they can be snipped out, zipped in, and 
presto-chango, no more problems with pest X or disease Y (or, for 
that matter, diabetes, overly tall or fat people, retarded people, or 
otherwise objectionable people).  Ah, what a world.  What power.  
What delicious arrogance.  The author of The Prince must be proud.

The reality, which I think will become increasingly "real" as our 
friends at "M" actually try to commercialize multi-genic trait 
products, is that genes interact.  I mean, "really" interact, and 
often in ways that are unintended and unpredictable.  The very notion 
of an independent "snip-zip-able" gene is actually a product of 
faulty, outdated science - yet this notion is the foundation of 
commercial GE today.

Our pals in the life science companies (another misnomer) have gotten 
away with it so far because they are working with single gene traits, 
and often, genes which already exist in a given species.  So, what is 
being inserted is another copy of the same gene but with very slight 
changes in it - so the plant can sometimes be "fooled" into letting 
it be.  Understand that plant cells have fantastically elaborate 
processes for constantly inspecting chromosome integrity, ever alert 
to detecting abnormalities and either excising them or silencing 
them.  See Mae Wan Ho's very readable book Genetic Engineering:  
Dream or Nightmare for a much more authoritative take on this.  

Understand also that "order matters" - that is to say, the particular 
place that a given transgene lands on a given chromosome influences 
its expression.  And both of the methods used by GE breeders to 
insert transgenes are entirely random.  They have no way (yet) of 
ensuring that the transgene(s) goes into a particular chromosome, 
let alone, at a particular insertion point.  So, they just make 
zillions of attempts, and then expend enormous effort to screen out 
the maladapted individuals from the cases where genes have 
successfully inserted.

But the point is, what will happen when the introduced genes are 
interacting not just "one-on-many" but "several-on-many"?  The 
potential for unintended side effects will be massively increased, 
given that it is the interactions that determine the product - not a 
single gene.  

And be clear, that the above phenomenon pertains whether the 
transgenes come from within or without the host species.  Case in 
point is the Arabidopsis example discussed earlier on this list.  
Find a naturally occurring mutation (in Arabidopsis) which confers 
herbicide resistance (chlorosulfuron, I think), pull it out and make 
it into a transgene, and then blast it back into other individuals 
(non mutant) of the same species.  What happens?  Transformed 
individuals express not just chlorosulfuron resistance, but are also 
changed from selfing to outcrossing species.  In its natural state, 
Arabidopsis has 0.3% outcrossing.  In transformed individuals, 
outcrossing increases to a range of degrees (up to 10%, if memory 
serves), depending on "where" in the chromosomes the transgenes 
insert.  And this is all in the same species.  

So, I am increasingly convinced that it is the process that is 
dysfunctional and indefensible - not just the products (the latter is 
the industry position).  Ann
ACLARK@plant.uoguelph.ca
Dr. E. Ann Clark
Associate Professor
Crop Science
University of Guelph
Guelph, ON  N1G 2W1
Phone:  519-824-4120 Ext. 2508
FAX:  519 763-8933
http://www.oac.uoguelph.ca/www/CRSC/faculty/eac.htm

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